Optical engines are commonly used to transfer electronic data at high rates of speed. An optical engine includes hardware for transferring an electrical signal to an optical signal, transmitting that optical signal, receiving the optical signal, and transforming that optical signal back into an electrical signal. The electrical signal is transformed into an optical signal when the electrical signal is used to modulate an optical source device such as a laser. The light from the source is then coupled into an optical transmission medium such as an optical fiber. After traversing an optical network through various optical transmission media and reaching its destination, the light is coupled into a receiving device such as a photo-detector. The photo-detector then produces an electrical signal based on the received optical signal for use by digital processing circuitry.
Circuitry that makes use of optical engines is often referred to as photonic circuitry. The various components that comprise a photonic circuit may include optical waveguides, optical amplifiers, lasers, and detectors. One common component used in photonic circuitry is a Vertical Cavity Surface Emitting Laser (VCSEL). Typically, multiple VCSELs are formed into a single chip and serve as light sources for optical transmission circuits. The light emitted by a VCSEL is typically focused into an optical transmission medium using a system of lenses.
This system of lenses may also act as either a multiplexer or demultiplexer. These components may be used for optical networks that utilize Wavelength Division Multiplexing (WDM) technology. WDM technology allows for transmission of several wavelengths of light through a single optical fiber. This provides several channels of communication across that single fiber and thus allows for a greater bandwidth. Bandwidth refers to the amount of data which can be transferred during a particular unit of time. In a WDM system, a multiplexer is used to divide a signal among multiple transmission mediums and a demultiplexer is used to combine multiple signals back into a single transmission medium.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.